Research On The Hydraulic Characteristics Of Inlet And Outlet System Of Urban Sewage Pumping Station

Urban sewage pumping station is one of the structures in municipal engineering and hydraulic engineering . The hydraulic characteristic of the inlet and outlet system which is an important part of urban sewage pumping station has a direct influence on the efficiency of the pump. In city , because the occupied area of the urban sewage pumping station is usually limited , the length of the forebay is inclined to be short and the diffusion angle in flow direction is big accordingly , which causes bad flow pattern, such as backflows ,vortices, etc. The bad flow pattern will make the efficiency of the pump unit drop. Meanwhile, because there are a lot of sediments in sewage in the forebay , the bad flow pattern will make sediments depositing freely and the sediment deposition will cause worse flow pattern.Siphon outlet piping can cut off the outlet flow safely and easily when the pump is stopped. It is of high value in application .Based on the hydraulic model test of Pudong north road pumping station in Shanghai, the hydraulic characteristics of the forebay were studied in the conditions of no diversion, the set-up of water-depressed plate and the set-ups of water-depressed plate and guide piers . Also, the hydraulic characteristic of the siphon outlet piping was studied. The conclusions from the paper were valuable in the design of those similar pumping stations.